The present invention relates to wear-resistant parts that have a higher solid state lubrication capability as well as a higher wear resistance and oxidization behavior.
In the field of cutting tools, molds and mechanical components, it is popular to coat various hard layers in order to have superior wear resistance, oxidation behavior and lubrication capability. Typical TiN, TiCN layers have good wear resistance, but they still have problems relating to sufficient oxidation resistance. Furthermore, TiAlN based layers proposed by Japanese laid-open patent specification Sho62-56565 and others have good wear resistance and oxidation behavior but lubrication capability is still low. CrN, CrCN based layers have good lubrication capability, but have lower layer hardness and lower wear resistance. Like the above, conventional layers are inferior in either wear resistance or oxidization behavior or lubrication properties and still have some problems in various applications. In addition, in order to have good lubrication properties, Japanese laid-open patent Hei 5-239618 and others proposed to coat a MoS based layer, which has better lubrication properties, on the surface of hard layers; however, wear properties are poor. Similarly, conventional layers still have a certain problem and in order to solve problems with layers other than MoS based layer, Japanese laid-open patent Hei 11-156992 proposed to coat a CrN based layer as the top layer on TiAlN based layers, but this coating is not yet satisfactory in wear resistance, because the thickness of a TiAlN layer is not enough, due to limitation of the entire layer thickness, to some extent.